Flameproof device for introduction or removal of fluid contents of a container

ABSTRACT

The invention is concerned with a flameproof device, e.g., a fitting or attachment, in the form of a cap or plug for closing the aperture between a transfer pipe, such as a dip pipe, and the rim of an opening or fitting, which may simply be an oversized mouth of a container into which the transfer pipe is inserted.

United States Patent [1 1 Stock June 19, 1973 FLAMEPROOF DEVICE FOR INTRODUCTION OR REMOVAL OF FLUID CONTENTS OF A CONTAINER [75] Inventor: Arthur Stock, Sunderland,

England [73] Assigneej Rohm and Haas Company,

Philadelphia, Pa.

[22] Filed: Sept. 10, 1970 [21] Appl. No.: 71,045

[52] US. Cl. 220/86, 141/286 [51] Int. Cl. B65b 3/18, 1367c 3/00 [58] Field of Search 48/192; 137/377,

137/588; 138/103; 141/59, 285, 286, 310, 311, 384, 392', 220/44 A, 86 R, 88 A; 222/189 [56] References Cited UNITED STATES PATENTS 1,982,879 12/1934 Overbury 220/86 R 2,208,989

7/1940 Lewis 141/285 1,155,070 9/1915 Kessler 220/86 1,611,922 12/1926 Lawton.... 220/36 3,291,165 12/1966 Fraylick 141/286 1,703,583 2/1929 Hathaway 220/44 A X 1,813,964 7/1931 Schubert 220/44 A 2,956,737 10/1960 I-lager 141/383 Primary Examiner-Herbert F. Ross Attorney-George F. W. Simmons and Carl A.

Castellan [5 7] ABSTRACT The invention is concerned with a flameproof device, e.g., a fitting or attachment, in the form of a cap or plug for closing the aperture between a transfer pipe, such as a dip pipe, and the rim of an opening or fitting, which may simply be an oversized mouth of a container into which the transfer pipe is inserted.

6 Claims, 4 Drawing Figures PAIENIEB .nm 9 ms FIG.

FLAMEPROOF DEVICE FOR INTRODUCTION OR REMOVAL OF FLUID CONTENTS OF A CONTAINER DESCRIPTION When material, particularly inflammable material, is transferred to and from containers such as drums and tankers great care has to be taken to prevent sparking and consequential explosion, for example as a result of a build up of static electricity. The device of the invention is designed not only to minimize the danger of explosion but also to contain any explosion that may occur. It must be pointed out however that the use of the device of the invention is not intended to replace other conventional precautionary measures, such as grounding of metal parts, but to supplement them.

According to one embodiment of the invention there is provided a conduit in the form of a plug or cap for tight fitting into the mouth or access opening of a container or onto a fitting providing an access opening in the container, the conduit, whether in the form of a plug or cap having an unobstructed internal bore or channel so dimensioned that when the conduit is mounted on the container for use a transfer pipe can be slidably passed through the channel of the conduit (whether plug or cap) into the container, the conduit having a vent opening or passage through the wall of the conduit, communicating the interior of the container with the exterior and provided with a flamearresting device.

The flame-arresting device can conveniently be a flame arresting screen such as a 28-mesh stainless steel screen.

The conduit device may take the form of a plug which may have an external thread so as to be adapted for screwing into the internally threaded mouth of a container normally fitted with a screw closure.

Alternatively, the conduit device may take the form of a cap, one end of which has a cylindrical peripheral portion adapted to be secured on an access fitting, such as a short nipple, attached to the container.

Plugs or caps according to the invention in either case are readily attachable and readily removable and may be used in conjunction with drums or tankers or indeed containers of any size.

The plugs or caps of the invention may be made from any convenient material. Preferably however they are made from an electrically conducting material so that there can be no electrical potential difference between the transfer pipe and the container (which is normally grounded in use). If the plug or cap is made from a nonconducting material then a conducting strip to electrically connect the transfer pipe and the container should be provided either separately or through the plug or cap. I

The devices of the invention may be used in connection with the transfer of any flowable material whether liquid or solid.

The devices may be fitted with a flange, lug, handle, or any other fitment to enable them more easily to be tightly fitted into or onto the mouth of a container.

One particularly convenient method of providing the internal bore or channel and the vent passage in a device according to the invention is to provide in the extending through the device a cylindrical bore of a diameter which increases, either gradually or stepwise, towards that end of the device to be fitted into or onto the container. In this case, in use, the smallest part of the bore or channel will be of a size to slidably fit on the a transfer pipe and there will then be a space or chamber,

usually annular, between the transfer pipe and the internal wall surface of the larger part of the bore. This usually annular space or chamber may then provide a part of the vent passage but there will nevertheless be required a passage communicating this space and the atmosphere.

The invention will now be more particularly described with reference to the accompanying drawing in which FIGS. 1 and 2 are axial and transverse sections respectively of a device (in the form of a plug) according to the invention for use in the transfer of liquid to or from a drum,

FIG. 3 is a section of a modification (in the form of a cap), and

FIG. 4 is another modification.

Referring to FIGS. 1 and 2 of the drawing, the conduit or plug 1, suitably made from stainless steel has an externally threaded portion 2 for screwing into the internally threaded mouth of a container (not shown). The plug has a stepped channel or bore 3, therethrough. The smaller part 4 of the channel is of a size to receive with a slidable fit a transfer tube or pipe (not shown). The larger part 5 of the bore will in use provide an annular passage, space, or chamber between the internal surface of that part of the bore and the transfer pipe. This annular passage will form the conjoined part of one or more vent openings or passages, such as the four shown at 6, 7, 8 and 9 radially bored through the plug from this (in use) annular passage. Each vent passage is screened. For example, a sleeve 10 of a 28-mesh stainless steel screen or of any screen of suitable flamearresting mesh is supported in the annular groove 11.

The device may be fitted with handles 12 to enable it to be more easily screwed into the container.

FIG. 3 shows a modification in which the lower end of conduit 1 is in the form of a cap adapted to be attached to a nipple 13 secured in the wall of a container 14 ro provide an access opening 15 therein. In this variation the end of the conduit 1 is provided with suitable means for being fastened to the nipple 13. As shown, there is an internal thread in the end of conduit 1 which engages an external thread on the nipple l3. Alternatively, these mating elements may be constructed in the form of mating elements of a conventional bayonet joint. Except for the modification of the lower end of the device to fit as a cap on a nipple providing an access opening in a container, the rest of the structure of the device may be the same as that shown in FIGS. 1 and 2.

FIGS. 4 shows the upper section; of another modification which may take the form either of a plug as in FIGS. 1 and 2 or as a cap in FIG. 3. In this embodiment, the internal wall of the channel or bore 3 may or may not be stepped. As shown, it has the same internal size throughout the length of the channel. Instead of depending on the sliding fit between a portion 4 of the bore and the external wall of the transfer tube 16 as in the embodiment of FIGS. 1 and 2, this tube is provided with a flange 17 rigidly fixed thereto, as by welding, and the lower face 18 of this flange is seated upon the face of the upper end of the conduit 1. The engagement may simply be the result of gravitational forces or it may involve magnetic attraction between the flange 17 and the upper end of conduit 1. Alternatively, the flange 17 may have an annular skirt l9 fastened to the upper end of conduit 1 by screw threads or by a conventional bayonet joint.

In FIG. 4, the annular chamber between the tube 16 and the internal wall 3 of the conduit 1 communicates with passages 6 and 8 for venting the interior of the drum or other container.

The embodiment of FIG. 4 may take the form of a plug as in FIGS. 1 and 2 or a cap as in FIG. 3.

I claim:

1. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical portion adapted to engage an access fitting in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged with the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical portion with the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, t least one opening radially extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and a flame-controlling screen disposed within the groove and extending over the aforesaid opening.

2. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical external peripheral portion adapted to engage an access fitting in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged within the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical peripheral portion within the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end of the conduit toward the other end thereof to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, the channel of the conduit being adapted to be closed adjacent the other end of the conduit by a mating surface on the transfer tube upon insertion of the latter into the channel, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the one opening or passage, intermediate the cylindrical peripheral portion and the other end of the conduit, extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and a flame-controlling screen disposed within the groove and extending over the aforesaid opening(s).

3. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical external peripheral portion adapted to engage an access fitting of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged within the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical peripheral portion within the access fitting of the container, the channel through the conduit being of large enough diameter throughout its length to allow insertion into, and removal from, the channel through its other end, of a transfer tube, a portion of the internal wall of the channel near the other end of the conduit having a closefitting sliding relationship with the external surface of the transfer tube so that the tube can be slidably inserted and removed, the remaining portion of the internal wall of the channel being of larger diameter, an annular groove on the external periphery of the conduit between the first-mentioned cylindrical external peripheral portion thereof and the other end thereof, at

least one opening, intermediate the cylindrical peripheral portion and the other end of the conduit, radially extending from the portion of the channel having the larger diameter through the wall of the conduit to the annular groove in its external periphery, and an annular screen disposed within the annular groove and over the aforesaid opening(s).

4. An attachment according to claim 1 in which the conduit has an end face against which a mating surface of a flange on the transfer tube is adapted to be seated.

5. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical internal peripheral portion adapted to engage the external periphery of an access nipple in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged with the nipple, means on the exterior of the conduit at said other end to facilitate the engagement of the cylindrical peripheral portion on the nipple of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and an annular flame-controlling screen disposed within the groove and extending over the aforesaid opening(s).

6. A readily removable attachment for aiding the transfer of liquid into or out of a'container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical portion adapted to engage an access fitting in a wall of a container so that the end of the conduit is outside the container when said portion of the attachment is engaged with the fitting, means on the exterior of the conduit at said other end to facilitate the engagement of the cylindrical portion within the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion. extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the chamber through the wall of the conduit to the annular groove, and a screen disposed within the annular groove over the openings. 

1. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical portion adapted to engage an access fitting in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged with the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical portion with the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, t least one opening radially extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and a flame-controlling screen disposed within the groove and extending over the aforesaid opening.
 2. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical external peripheral portion adapted to engage an access fitting in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged within the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical peripheral portion within the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end of the conduit toward the other end thereof to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, the channel of the conduit being adapted to be closed adjacent the other end of the conduit by a mating surface on the transfer tube upon insertion of the latter into the channel, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the one opening or passage, intermediate the cylindrical peripheral portion and the other end of the conduit, extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and a flame-controlling screen disposed within the groove and extending over the aforesaid opening(s).
 3. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical external peripheral portion adapted to engage an access fitting of a container so that the other end of the conduit is outside the container when said porTion of the attachment is engaged within the fitting, means on the exterior of the conduit at said one end to facilitate the engagement of the cylindrical peripheral portion within the access fitting of the container, the channel through the conduit being of large enough diameter throughout its length to allow insertion into, and removal from, the channel through its other end, of a transfer tube, a portion of the internal wall of the channel near the other end of the conduit having a close-fitting sliding relationship with the external surface of the transfer tube so that the tube can be slidably inserted and removed, the remaining portion of the internal wall of the channel being of larger diameter, an annular groove on the external periphery of the conduit between the first-mentioned cylindrical external peripheral portion thereof and the other end thereof, at least one opening, intermediate the cylindrical peripheral portion and the other end of the conduit, radially extending from the portion of the channel having the larger diameter through the wall of the conduit to the annular groove in its external periphery, and an annular screen disposed within the annular groove and over the aforesaid opening(s).
 4. An attachment according to claim 1 in which the conduit has an end face against which a mating surface of a flange on the transfer tube is adapted to be seated.
 5. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical internal peripheral portion adapted to engage the external periphery of an access nipple in a wall of a container so that the other end of the conduit is outside the container when said portion of the attachment is engaged with the nipple, means on the exterior of the conduit at said other end to facilitate the engagement of the cylindrical peripheral portion on the nipple of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the container when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the chamber through the wall of the conduit to the annular groove in its external periphery, and an annular flame-controlling screen disposed within the groove and extending over the aforesaid opening(s).
 6. A readily removable attachment for aiding the transfer of liquid into or out of a container comprising a conduit having an unobstructed channel extending throughout its length and having at one end a cylindrical portion adapted to engage an access fitting in a wall of a container so that the end of the conduit is outside the container when said portion of the attachment is engaged with the fitting, means on the exterior of the conduit at said other end to facilitate the engagement of the cylindrical portion within the access fitting of the container, the channel through the conduit being only large enough at said other end to allow a sliding fit insertion into, and removal from, the channel through its other end, of a transfer tube and being large enough along at least that portion of its length extending from said one end toward the other end to provide an annular venting chamber circumscribed between the transfer tube and the channel portion extending from said one end and communicating with the interior of the contAiner when the attachment is fitted thereon and the transfer tube is positioned therein, said chamber being present only when said transfer tube is fully engaged in said attachment, an annular groove on the external periphery of the conduit radially aligned with said chamber, at least one opening radially extending from the chamber through the wall of the conduit to the annular groove, and a screen disposed within the annular groove over the openings. 